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Retirement Plans And Other Postretirement Benefits (Reconciliation Of Changes In Benefit Obligations And Plan Assets) (Details) - USD ($) $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Oct. 31, 2023 | Feb. 09, 2022 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Pension Benefits |  |  |  |  |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |  |
Benefit obligation, beginning of year |  |  | $ 248,114 | $ 316,169 |
Service cost |  |  | 0 | 0 | $ 0
Interest cost |  |  | 9,623 | 8,945 | 8,398
Effect of actuarial (gains) losses related to the following: |  |  |  |  |
Discount rate change |  |  | (10,751) | (61,519) |
Other |  |  | (6,459) | 1,513 |
Plan participant contributions |  |  | 0 | 0 |
Benefits paid |  |  | 16,957 | 16,994 |
Settlement payments and annuity purchase |  |  | (221,970) | 0 |
Benefit obligation, end of year |  |  | 1,600 | 248,114 | 316,169
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |
Plan assets at fair value, beginning of year |  |  | 218,119 | 244,612 |
Actual return on plan assets |  |  | (7,053) | (59,683) |
Employer contributions | $ 27,700 | $ 50,000 | 27,861 | 50,184 |
Plan participant contributions |  |  | 0 | 0 |
Benefits paid |  |  | 16,957 | 16,994 |
Settlement payments and annuity purchase |  |  | (221,970) | 0 |
Plan assets at fair value, end of year |  |  | 0 | 218,119 | 244,612
Funded status of the plans |  |  | (1,600) | (29,995) |
Amounts recognized in the consolidated balance sheets: |  |  |  |  |
Net amount recognized |  |  | 1,600 | 29,995 |
Other Post-Retirement Benefits |  |  |  |  |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |  |
Benefit obligation, beginning of year |  |  | 5,726 | 7,370 |
Service cost |  |  | 10 | 18 | 21
Interest cost |  |  | 288 | 207 | 195
Effect of actuarial (gains) losses related to the following: |  |  |  |  |
Discount rate change |  |  | 99 | (1,483) |
Other |  |  | 12 | 90 |
Plan participant contributions |  |  | 490 | 554 |
Benefits paid |  |  | 913 | 1,030 |
Settlement payments and annuity purchase |  |  | 0 | 0 |
Benefit obligation, end of year |  |  | 5,712 | 5,726 | 7,370
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |
Plan assets at fair value, beginning of year |  |  | 0 | 0 |
Actual return on plan assets |  |  | 0 | 0 |
Employer contributions |  |  | 423 | 476 |
Plan participant contributions |  |  | 490 | 554 |
Benefits paid |  |  | 913 | 1,030 |
Settlement payments and annuity purchase |  |  | 0 | 0 |
Plan assets at fair value, end of year |  |  | 0 | 0 | $ 0
Funded status of the plans |  |  | (5,712) | (5,726) |
Amounts recognized in the consolidated balance sheets: |  |  |  |  |
Net amount recognized |  |  | 5,712 | 5,726 |
Accrued Expenses | Pension Benefits |  |  |  |  |
Amounts recognized in the consolidated balance sheets: |  |  |  |  |
Accrued expenses (current) |  |  | 180 | 180 |
Accrued Expenses | Other Post-Retirement Benefits |  |  |  |  |
Amounts recognized in the consolidated balance sheets: |  |  |  |  |
Accrued expenses (current) |  |  | 489 | 489 |
Other Noncurrent Liabilities [Member] | Pension Benefits |  |  |  |  |
Amounts recognized in the consolidated balance sheets: |  |  |  |  |
Pension and other postretirement benefit obligations, net |  |  | 1,420 | 29,815 |
Other Noncurrent Liabilities [Member] | Other Post-Retirement Benefits |  |  |  |  |
Amounts recognized in the consolidated balance sheets: |  |  |  |  |
Pension and other postretirement benefit obligations, net |  |  | $ 5,223 | $ 5,237 |

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